Suchergebnisse

The identification of fuel-related practices in archaeological contexts is almost always associated with the identification of fire-related structures. Charcoal analysis is the standard method of identifying wood use in the past; however, in many circumstances wood was not the primary source of fuel. In arid and semi-arid environments alternative fuels such as dung, chaff and straw and, in general, plant processing by-products were predominant. The study of these types of fuel often necessitates the application of multi-proxy analyses, involving botanical micro-remains and geochemistry. This paper presents the results of an integrated analysis of phytoliths and chemical elements of samples collected in a modern ethnographic context, a domestic compound, in North Gujarat, India. Alternative fuels have been and are still very important in this area due to the scarcity of wood and the recent ban on cutting trees imposed by the government. Within the house studied, three fireplaces were present where different types of activities were performed selectively. The differential use of fuels in the three fireplaces is highlighted by the results of descriptive and multivariate statistics. However, the opposite geochemical signals that the fireplaces produced, when they should have been similar, would be difficult to interpret in an archaeological context where the practices that had produced such signals are unknown. The combination of phytoliths and geochemistry, coupled with the ethnographic information on the activity, can help us to construct better models to help interpret the archaeological record. ; This research was carried out within the framework of the projects MoMArq (Spanish Ministry of Economy and Competitiveness, HAR2014-55518-P) and NoGAP (Ministry of Economy and Competitiveness HAR2010-16052 and CONSOLIDER INGENIO CSD2010-00034; the Spanish Ministry of Education, Culture and Sport through the Program Ayudas para Proyectos Arqueologicos en el Exterior 2009–2010; and the EXCAVA 2009 program of the Generalitat de Catalunya). JJGG was supported by a JAE PreDOC Doctoral Scholarship (Spanish National Research Council and European Fund).

The planet Neptune and its largest moon Triton hold the keys to major advances across multiple fields of Solar System science. The ice giant Neptune played a unique and important role in the process of Solar System formation, has the most meteorologically active atmosphere in the Solar System (despite its great distance from the Sun), and may be the best Solar System analogue of the dominant class of exoplanets detected to date. Neptune's moon Triton is very likely a captured Kuiper Belt object, holding the answers to questions about the icy dwarf planets that formed in the outer Solar System. Triton is geologically active, has a tenuous nitrogen atmosphere, and is predicted to have a subsurface ocean. However, our exploration of the Neptune system remains limited to a single spacecraft flyby, made by Voyager 2 in 1989. Here, we present the high-level science case for further exploration of this outermost planetary system, based on a white paper submitted to the European Space Agency (ESA) for the definition of the second and third large missions in the ESA Cosmic Vision Programme 2015–2025. We discuss all the major science themes that are relevant for further spacecraft exploration of the Neptune system, and identify key scientific questions in each area. We present an overview of the results of a European-led Neptune orbiter mission analysis. Such a mission has significant scope for international collaboration, and is essential to achieve our aim of understanding how the Solar System formed, and how it works today.